Gustav is bearing down on Jamaica after leaving 67 people dead in Haiti and the Dominican Republic.

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Forecasters said parts of Jamaica could get 25 inches of rain, which could trigger landslides and cause serious crop damage.

Grand Cayman is bracing for a possible strike Friday. A resort owner said Gustav doesn't look as threatening as Hurricane Ivan, which destroyed 70 percent of the island's buildings four years ago.

Gulf Coast Prepares

Gustav is projected to hit the Gulf Coast at the end of Labor Day weekend, and it could be a Category 3 storm by then. Forecasters caution it's difficult to predict the storm's path this early.

Along the U.S. Gulf Coast, preparations are under way. Louisiana and Texas have put their national guards on standby. On Thursday, Mississippi Gov. Haley Barbour declared a station of emergency, reported WAPT-TV in Jackson, Miss.

?I urge all Mississippians to please take this storm seriously," Barbour said. "One of the most important lessons we learned after Hurricane Katrina was that there is no substitute for awareness and self-help, especially in the days before a hurricane is predicted to hit. Now is the time to prepare yourself, your family and your friends.?

Meanwhile, officials in New Orleans said a mandatory evacuation may be necessary and warned that there won't be a massive shelter at the Superdome this time.

Instead, the state has arranged for buses and trains to take about 30,000 people to safety. Nearly 8,000 people are already signed up for transportation help.

Tropical Storm Hanna Forms

The National Hurricane Center said Tropical Storm Hanna has formed northeast of the northern Leeward Islands in the Atlantic.

Hanna, the eighth tropical storm of the Atlantic season, had top sustained winds near 40 mph Thursday.

Hanna could produce rainfall of 1 to 4 inches across parts of the Leeward Islands. It's too soon to say if Hanna will affect the United States.